A new fluorescent probe can monitor milk safety

Scientists have invented a fluorescent probe to measure fat levels in milk, according to Chemistry World. Fat content is associated with the levels of protein and vitamins in milk so it’s a good way to gauge its quality. But existing testing options are either cheap but limited or expensive and complicated. Some even require potentially toxic substances and specialist training.

Young-Tae Chang and his team at the National University of Singapore wanted to develop a device that was accurate, easy to use, and affordable, so it could be used by anyone from dairy farmers to people unsure about that last pint in their fridge.

So they came up with a system that uses a probe they’ve called Milk Orange. This uses a non-toxic dye called hydrophobic boron dipyrromethene. When dipped into milk, it transmits fluorescent signals which glow brighter and spread out more the greater the concentration of fat in the milk.

More than six billion people around the world drink milk on a regular basis, not all of it pasteurised, so it would be very useful to bring Milk Orange to market, especially in developing countries or other areas where no reliable testing exists. It hasn’t yet been trialled with different animal milks, but Chang and his researchers are working to make a handheld version of the probe available in India as quickly as possible.